Namenode格式和在hadoop2.2.0中启动namenode

Question

我试图安装单节点配置，我成功地下载和解压缩tar和编辑所有配置文件，但在格式化namenode时遇到了问题。

这些错误是：

14/07/14 02:56:40 WARN fs.FileUtil: Failed to delete file or dir [/home/renu123/yarn/yarn_data/hdfs/namenode/current/seen_txid]: it still exists.
14/07/14 02:56:40 WARN fs.FileUtil: Failed to delete file or dir [/home/renu123/yarn/yarn_data/hdfs/namenode/current/VERSION]: it still exists.
14/07/14 02:56:40 WARN fs.FileUtil: Failed to delete file or dir [/home/renu123/yarn/yarn_data/hdfs/namenode/current/fsimage_0000000000000000000]: it still exists.
14/07/14 02:56:40 WARN fs.FileUtil: Failed to delete file or dir [/home/renu123/yarn/yarn_data/hdfs/namenode/current/fsimage_0000000000000000000.md5]: it still exists.
14/07/14 02:56:40 FATAL namenode.NameNode: Exception in namenode join
java.io.IOException: Cannot remove current directory: /home/renu123/yarn/yarn_data/hdfs/namenode/current
    at org.apache.hadoop.hdfs.server.common.Storage$StorageDirectory.clearDirectory(Storage.java:299)
    at org.apache.hadoop.hdfs.server.namenode.NNStorage.format(NNStorage.java:523)
    at org.apache.hadoop.hdfs.server.namenode.NNStorage.format(NNStorage.java:544)
    at org.apache.hadoop.hdfs.server.namenode.FSImage.format(FSImage.java:147)
    at org.apache.hadoop.hdfs.server.namenode.NameNode.format(NameNode.java:837)
    at org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:1213)
    at org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:1320)
14/07/14 02:56:40 INFO util.ExitUtil: Exiting with status 1
14/07/14 02:56:40 INFO namenode.NameNode: SHUTDOWN_MSG: 
/************************************************************
SHUTDOWN_MSG: Shutting down NameNode at ubuntu/127.0.1.1
************************************************************/

在google上搜索之后，我通过切换到根帐户格式化了namenode，如下所示：

root@ubuntu:~/yarn/yarn_data/hdfs/namenode# hdfs namenode -format
Re-format filesystem in Storage Directory /home/renu123/yarn/yarn_data/hdfs/namenode ? (Y or N) Y
14/07/14 02:59:30 INFO common.Storage: Storage directory /home/renu123/yarn/yarn_data/hdfs/namenode has been successfully formatted.
14/07/14 02:59:30 INFO namenode.FSImage: Saving image file /home/renu123/yarn/yarn_data/hdfs/namenode/current/fsimage.ckpt_0000000000000000000 using no compression
14/07/14 02:59:30 INFO namenode.FSImage: Image file /home/renu123/yarn/yarn_data/hdfs/namenode/current/fsimage.ckpt_0000000000000000000 of size 196 bytes saved in 0 seconds.
14/07/14 02:59:30 INFO namenode.NNStorageRetentionManager: Going to retain 1 images with txid >= 0
14/07/14 02:59:30 INFO util.ExitUtil: Exiting with status 0
14/07/14 02:59:30 INFO namenode.NameNode: SHUTDOWN_MSG:
/************************************************************
SHUTDOWN_MSG: Shutting down NameNode at ubuntu/127.0.1.1
************************************************************/

即使在格式化之后，我仍然可以看到hdfs/namenode文件夹中的目录。

假设对namenode进行了格式化，我进一步尝试使用命令start-dfs.sh启动namenode，但未能启动。

这是从usr/local/hadoop/logs获取的日志：

2014-07-14 02:49:10,478 WARN org.apache.hadoop.hdfs.server.common.Storage: Cannot access storage directory /home/renu123/yarn/yarn_data/hdfs/namenode
2014-07-14 02:49:10,484 INFO org.mortbay.log: Stopped SelectChannelConnector@0.0.0.0:50070
2014-07-14 02:49:10,585 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl: Stopping NameNode metrics system...
2014-07-14 02:49:10,585 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl: NameNode metrics system stopped.
2014-07-14 02:49:10,586 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl: NameNode metrics system shutdown complete.
2014-07-14 02:49:10,587 FATAL org.apache.hadoop.hdfs.server.namenode.NameNode: Exception in namenode join
org.apache.hadoop.hdfs.server.common.InconsistentFSStateException: Directory /home/renu123/yarn/yarn_data/hdfs/namenode is in an inconsistent state: storage directory does not exist or is not accessible.
    at org.apache.hadoop.hdfs.server.namenode.FSImage.recoverStorageDirs(FSImage.java:292)
    at org.apache.hadoop.hdfs.server.namenode.FSImage.recoverTransitionRead(FSImage.java:200)
    at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.loadFSImage(FSNamesystem.java:787)
    at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.loadFromDisk(FSNamesystem.java:568)
    at org.apache.hadoop.hdfs.server.namenode.NameNode.loadNamesystem(NameNode.java:443)
    at org.apache.hadoop.hdfs.server.namenode.NameNode.initialize(NameNode.java:491)
    at org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:684)
    at org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:669)
    at org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:1254)
    at org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:1320)
2014-07-14 02:49:10,590 INFO org.apache.hadoop.util.ExitUtil: Exiting with status 1
2014-07-14 02:49:10,602 INFO org.apache.hadoop.hdfs.server.namenode.NameNode: SHUTDOWN_MSG: 

帮我找到解决办法。

我的配置文件

core-site.xml

<configuration>
<property>
   <name>fs.default.name</name>

   <value>hdfs://localhost:9000</value>
</property>
</configuration>

yarn-ste.xml

<configuration>
<!-- Site specific YARN configuration properties -->
<property>
   <name>yarn.nodemanager.aux-services</name>

   <value>mapreduce_shuffle</value>
</property>
<property>
   <name>yarn.nodemanager.aux-services.mapreduce.shuffle.class</name>

   <value>org.apache.hadoop.mapred.ShuffleHandler</value>
</property>
</configuration>

mapred-site.xml

<configuration>
<property>
   <name>mapreduce.framework.name</name>

   <value>yarn</value>
</property>
</configuration>

hdfs-site.xml

<configuration>
<property>
   <name>dfs.replication</name>

   <value>1</value>
 </property>
 <property>
   <name>dfs.namenode.name.dir</name>

   <value>file:/home/renu123/yarn/yarn_data/hdfs/namenode</value>
 </property>
 <property>
   <name>dfs.datanode.data.dir</name>

   <value>file:/home/renu123/yarn/yarn_data/hdfs/datanode</value>
 </property>
</configuration>

Answer 1

中使用的file关键字可能存在问题。

<configuration>
<property>
   <name>dfs.replication</name>

   <value>1</value>
 </property>
 <property>
   <name>dfs.namenode.name.dir</name>

   **<value>file:/home/renu123/yarn/yarn_data/hdfs/namenode</value>**
 </property>
 <property>
   <name>dfs.datanode.data.dir</name>

   **<value>file:/home/renu123/yarn/yarn_data/hdfs/datanode</value>**
 </property>
</configuration>

您可能需要删除这个“文件：”并指定如下所示

/home/renu123/yarn/yarn_data/hdfs/namenode

和

/home/renu123/yarn/yarn_data/hdfs/datanode

Answer 2

@Renukeshwar，我也有同样的问题。如果您查看错误日志中的这些行，

java.io.IOException:Cannot remove directory:/home/renu123/yarn/yarn_data/hdfs/namenode/current
java.io.IOException: Cannot create directory: /home/renu123/yarn/yarn_data/hdfs/namenode/current

当当前用户没有对该文件夹的读写访问权限时，就会发生这种情况。

溶液

在更改所有.xml文件中的所有配置后，请在终端中键入此配置。这使组hduser的用户hadoop可以访问文件夹。

sudo chown -R hduser:hadoop /usr/local/hadoop

注意:要检查哪个组用户属于哪个组，输入groups your-username-here

编辑:您可能必须删除tmp目录。

sudo rm -R /path-to-your-common-storage

Answer 3

如果您遵循了链接中给出的安装步骤(@Vikas link正在工作，只需忽略附加的‘最后-可能是错误:) - https://www.digitalocean.com/community/tutorials/how-to-install-hadoop-on-ubuntu-13-10)

那么下面应该适合你了。

解决方案

sudo chown -R hduser:hadoop /usr/local/hadoop
sudo chown -R hduser:hadoop /usr/local/hadoop_store

如果有任何问题，请确保您已经为hadoop用户正确地更改了.bashrc文件，这对我是有效的。